A method of forming a confined crystallization multilayer film includes coextruding a plurality of first polymer layers and a plurality of second polymer layer to form a multilayer film wherein each first polymer layer is sandwiched between second polymer layers and axially orienting the multilayer film at a temperature below the melting temperature (T.sub.m) of the second polymer layer and to a thickness such that each first polymer layer forms a high aspect ratio substantially crystalline lamellae.

Exfoliation of graphene from graphite using multilayer coextrusion is generally disclosed. In some example embodiments, graphite may be dispersed within a first processing material, and the first processing material and a second processing material may be co-extruded through a plurality of series coupled layer multiplication dies to exfoliate graphene from the graphite. The graphene may be separated from the resulting multi-layered material. In some example embodiments, graphite flake and/or expanded graphite may be dispersed within the first processing material.

Apparatus and method for amplifying laser signals using segments of fibers of differing core diameters and/or differing cladding diameters to suppress amplified spontaneous emission and non-linear effects such as four-wave mixing (FWM), self-phase modulation, and stimulated Brillouin and/or Raman scattering (SBS/SRS). In some embodiments, different core sizes have different sideband spacings (spacing between the desired signal and wavelength-shifted lobes). Changing core sizes and providing phase mismatches prevent buildup of non-linear effects. Some embodiments further include a bandpass filter to remove signal other than the desired signal wavelength and/or a time gate to remove signal at times other than during the desired signal pulse. Some embodiments include photonic-crystal cores for the signal and/or photonic-crystal inner cladding for the pump and/or use reflector connector segments. Some embodiments include an inner glass cladding to confine the signal in the core and an outer glass cladding to confine pump light in the inner cladding.

A bioabsorbable scaffold composed of a multilayer structure of alternating layers of different polymers is disclosed. The multilayer structure can have 20 to 1000 layers and the individual thickness of the layers can be 0.2 to 5 microns. A method of making the scaffold including a layer multiplying extrusion process is disclosed.